Humans and animals in general, are exposed to many toxic compounds that contaminate the environment, food chain, water supply and various items that are part of everyday life. These range in number, type and exposure from ingredients in toothpaste and shampoos to drugs and pathogens in well-water. Amongst Canadian First Nation and Inuit populations, environmental toxins are risk factors for other highly prevalent diseases, especially type 2 diabetes [Sharp D. Environmental toxins, a potential risk factor for diabetes among Canadian Aboriginals. Int J Circumpolar Health. 2009; 68(4):316-26]. A large over-the-counter consumer market has arisen under the guise of ‘detox’, but most of the products have no rationale or clinical evidence to support their use. The concept of detox has great appeal to consumers, both the health-conscious and others concerned with the growing number of stories in the media about pollution and diseases related to toxic substances. Thus, there is substantial interest in this area, few effective products and a growing need.
The replenishment or boosting of the beneficial organisms through administration of probiotics has become feasible in Canada relatively recently, and has led to much interest amongst consumer and healthcare professionals. Indeed, probiotics are one of the fastest growing food segments in North America. However, gaining insight into the mechanisms by which indigenous microbes and exogenous probiotics affect the subject has been limited.
Probiotic Lactobacilli and bifidobacteria have been shown to help manage several gut pathologies. For example, U.S. Pat. No. 6,641,808 disclosing the use of Lactobacilli for the treatment of obesity; U.S. Pat. No. 5,531,988, discloses a mixture of an immunoglobulin and a bacterium, such as Lactobacilli or bifidobacterium or mixtures thereof, that may be used to treat diarrhea, constipation, and gas/cramps; U.S. Pat. No. 6,080,401 discloses a combination of probiotics having Lactobacillus acidophilus and Bifidobacterium bifidus and herbal preparations for aiding in weight loss, and so forth.
The ability of probiotic products to ameliorate toxins has been much less studied, but nevertheless has some foundation. For example, Lactobacilli and/or bifidobacteria have been found to alter the subjects intestinal metabolic signature [Ndagijimana, M. Laghi L, Vitali B, Placucci G, Brigidi P, Guerzoni M E. Effect of synbiotic food consumption on human gut metabolic profiles evaluated by 1H nuclear magnetic resonance spectroscopy. Int J Food Microbiol. 2009; 134: 147-153]; bind to aflatoxin (Lactobacillus strains) [Hernandez-Mendoza A, Garcia H S, Steele J L. Screening of Lactobacillus casei strains for their ability to bind aflatoxin B1. Food Chem Toxicol. 2009; 47(6):1064-8]; and detoxify or bind and negate other mycotoxins (B. animalis) [Fuchs S, Sontag G, Stidl R, Ehrlich V, Kundi M, Knasmüller S. Detoxication of patulin and ochratoxin A, two abundant mycotoxins, by lactic acid bacteria. Food Chem Toxicol. 2008; 46(4):1398-407].
In summary, the problem associated with toxic compounds is real, and of growing concern to consumers.
Heavy Metals
Heavy metal toxicity is one of the largest health risks in the 21st century. Consumption of lead and cadmium through environmental exposure and diet has been directly responsible for poor health outcomes including: impaired neurological function and loss of IQ, osteoporosis, lung and kidney cancer.
Heavy metals such as lead and cadmium are present in the natural environment, and therefore many bacteria over time have developed mechanisms of resistance to these metals which generally include actively precipitating and sequestering the metals intra/extra cellular or the active efflux of metals out of the cell cytoplasm. Non-food grade bacteria have been investigated for their use in sequestration and detoxification of heavy metals and have shown success (JS Singh et al. Genetically engineered bacteria: An emerging tool for environmental remediation and future research perspectives. Gene. July 2011. 40 (1-2):1-9); Rajkumar et al. Potential of siderophore-producing bacteria for improving heavy metal phytoextraction. Trends Biotechnol. March 2010. 28 (3):142-149).
Mercury
Mercury is one of the most toxic substances known to man and its consumption by a subject is linked to poor health outcomes including altered neurological development in children. Yet, North Americans and Europeans are estimated to consume 6.7 μg daily of inorganic mercury and methylmercury (World Health Organization, 1991).
Mercury is present in the natural environment, and as such, many bacteria have adopted mechanisms of resistance to it, which generally reduce mercury levels in the surrounding environment. Many non-food grade bacteria have been investigated for their use in sequestration and detoxification of mercury and mercury compounds in the environment, however the application of food grade bacteria has not been demonstrated to date.
Arsenic
Arsenic is a metalloid element which commonly comes in two oxidation states: arsenate (As V) and arsenite (As III). Arsenic is found distributed globally often in the earth's crust, it is highly soluble in water and is found in high concentrations in ground water. Arsenic toxicity has been linked to a number of cases and is known to cause organ failure, cancer and death. Main routes of exposure is through ingestion via diet, often arsenic contaminated waters are used for irrigation of farmland resulting in accumulation of the metal in plants and food.
Pesticides
Pesticides such as malathion and parathion fall into the class of organophosphate compounds and act as cholinesterase inhibitors. Malathion is one of the most widely used pesticides in the U.S., and parathion use has recently been limited and is not used in many developed nations due to high toxicity. However, produce imports still consistently detect levels of parathion on produce and it is used in some rare instances in North America.
Major routes of public exposure is through consumption via diet. Agricultural workers and industrial workers are at increased risk of exposure through work place by absorption or inhalation if safety protocols not properly followed.
In view of the problems associated to the exposure of any of the above toxic compounds, it would be advantageous to provide for food grade bacteria that can sequester toxic compounds, including heavy metals, mercury, arsenic, pesticides, such as malathion and parathion, or a combination thereof, from the gastrointestinal tract of a subject to reduce the amount of the toxic compound available to be absorbed by the subject, while detoxifying the toxic compounds directly reduces the toxicity of toxic compounds available to be absorbed by the subject.